The automatic conversion of text to synthetic speech is commonly known as text to speech (TTS) conversion or text to speech (TTS) synthesis. A number of different techniques have been developed to make TTS conversion practical on a commercial basis. An excellent article on the history of TTS development, as well as the state of the art in 1987, is Dennis H. Klatt, Review of text-to-speech conversion for English, Journal of the Acoustical Society of America vol. 82(3), September 1987, hereby incorporated by reference. A number of commercial products use TTS techniques, including the Speech Plus Prose 2000 (made by the assignee of the applicants), the Digital Equipment DECTalk, and the Infovox SA-101.